INFO: task kworker/u8:11:4268 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:11 state:D stack:21640 pid:4268 tgid:4268 ppid:2 task_flags:0x4248060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7421
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7612
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7649
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
mark_inode_dirty_sync include/linux/fs.h:2215 [inline]
dquot_alloc_space_nofail include/linux/quotaops.h:298 [inline]
dquot_alloc_block_nofail include/linux/quotaops.h:324 [inline]
ext4_new_meta_blocks+0x2f8/0x410 fs/ext4/balloc.c:762
ext4_ext_grow_indepth fs/ext4/extents.c:1330 [inline]
ext4_ext_create_new_leaf fs/ext4/extents.c:1434 [inline]
ext4_ext_insert_extent+0x14fd/0x4bf0 fs/ext4/extents.c:2135
ext4_ext_map_blocks+0x15bf/0x5480 fs/ext4/extents.c:4490
ext4_map_create_blocks+0x116/0x530 fs/ext4/inode.c:699
ext4_map_blocks+0xe27/0x1970 fs/ext4/inode.c:935
mpage_map_one_extent fs/ext4/inode.c:2502 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2592 [inline]
ext4_do_writepages+0x240f/0x44c0 fs/ext4/inode.c:3068
ext4_writepages+0x1fe/0x4e0 fs/ext4/inode.c:3162
do_writepages+0x338/0x560 mm/page-writeback.c:2560
__writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1800
writeback_sb_inodes+0x9de/0x1af0 fs/fs-writeback.c:2111
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2187
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2298
wb_check_old_data_flush fs/fs-writeback.c:2402 [inline]
wb_do_writeback fs/fs-writeback.c:2481 [inline]
wb_workfn+0xc92/0x10f0 fs/fs-writeback.c:2509
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task jbd2/sda1-8:4940 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8 state:D stack:23648 pid:4940 tgid:4940 ppid:2 task_flags:0x240040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_buffer include/linux/buffer_head.h:476 [inline]
jbd2_journal_commit_transaction+0x2f6e/0x5c80 fs/jbd2/commit.c:834
kjournald2+0x3bc/0x740 fs/jbd2/journal.c:200
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz-executor:5597 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22184 pid:5597 tgid:5597 ppid:5596 task_flags:0x440100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7421
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7612
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7649
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2483
ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7834
do_page_mkwrite+0x147/0x310 mm/memory.c:3890
wp_page_shared mm/memory.c:4291 [inline]
do_wp_page+0x1a85/0x4b60 mm/memory.c:4514
handle_pte_fault mm/memory.c:6684 [inline]
__handle_mm_fault mm/memory.c:6809 [inline]
handle_mm_fault+0x15c1/0x3540 mm/memory.c:6976
do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fbef047cae2
RSP: 002b:00007ffc0969bd00 EFLAGS: 00010202
RAX: 00007fbeee570000 RBX: 000055558ffec5b0 RCX: 0000000000000006
RDX: 0000000000002e3a RSI: 000055559006b368 RDI: 0000000000000040
RBP: 00007ffc0969c200 R08: 000055559006b460 R09: 00000000000000a2
R10: 0000000000004000 R11: 0000000000000001 R12: 00007ffc0969c040
R13: 00007ffc0969be30 R14: 585858582e7a7973 R15: 00007ffc0969bd80
INFO: task syz.9.3067:14869 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.3067 state:D stack:25576 pid:14869 tgid:14869 ppid:11588 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7421
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7612
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7649
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2483
ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7834
do_page_mkwrite+0x147/0x310 mm/memory.c:3890
do_shared_fault mm/memory.c:6183 [inline]
do_fault mm/memory.c:6245 [inline]
do_pte_missing+0x70f/0x3570 mm/memory.c:4774
handle_pte_fault mm/memory.c:6660 [inline]
__handle_mm_fault mm/memory.c:6809 [inline]
handle_mm_fault+0x1a2a/0x3540 mm/memory.c:6976
do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7f178ce72c09
RSP: 002b:00007ffde35eae80 EFLAGS: 00010202
RAX: 0000001b30d24000 RBX: 0000000000000000 RCX: 00000000003ffde8
RDX: 0000001b30d23ffc RSI: 00000000003ffde8 RDI: 00007f178dd55700
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f178d212000
R10: 00007f178dd55700 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000014ccb R14: ffffffff816db6ae R15: 00007f178dd55720
INFO: task syz.5.3089:14909 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.3089 state:D stack:26936 pid:14909 tgid:14909 ppid:6915 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7421
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7612
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7649
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2281 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2073 [inline]
call_mmap_prepare mm/vma.c:2913 [inline]
__mmap_region mm/vma.c:3030 [inline]
mmap_region+0xef7/0x2840 mm/vma.c:3128
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x272/0x4e0 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0f6579e2c2
RSP: 002b:00007ffde6f5c788 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b34564000 RCX: 00007f0f6579e2c2
RDX: 0000000000000003 RSI: 00000000005c0000 RDI: 0000001b34564000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 00000000000001fb
R13: 00000000000927c0 R14: 0000000000053406 R15: 00007ffde6f5ca60
INFO: task syz.1.3079:14910 blocked in I/O wait for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3079 state:D stack:26936 pid:14910 tgid:14910 ppid:12369 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5820 kernel/sched/core.c:7385
__schedule_loop kernel/sched/core.c:7462 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7477
io_schedule+0x7f/0xd0 kernel/sched/core.c:8149
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7421
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7612
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7649
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2281 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2073 [inline]
call_mmap_prepare mm/vma.c:2913 [inline]
__mmap_region mm/vma.c:3030 [inline]
mmap_region+0xef7/0x2840 mm/vma.c:3128
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x272/0x4e0 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f77fb59e2c2
RSP: 002b:00007fff276459d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b30764000 RCX: 00007f77fb59e2c2
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b30764000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 0000000000000090
R13: 00000000000927c0 R14: 00000000000534bb R15: 00007fff27645cb0
Showing all locks held in the system:
locks held by khungtaskd/34: 1, last CPU#0:
#0: ffffffff8fd5a2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8fd5a2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8fd5a2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:11/4268: 6, on CPU#0:
#0: ffff888021af4148 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888021af4148 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888021af4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff888021af4148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc9000f7a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000f7a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000f7a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc9000f7a7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff8880370d80e8 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:670
#3: ffff8880370eccd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1f1/0x4e0 fs/ext4/inode.c:3161
#4: ffff888036276950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
#5: ffff8880761eb878 (&ei->i_data_sem#2){++++}-{4:4}, at: ext4_map_blocks+0xa32/0x1970 fs/ext4/inode.c:921
locks held by getty/5375: 2, on CPU#1:
#0: ffff888033fc20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032362e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5597: 3, on CPU#0:
#0: ffff88807d22a448 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:309
#1: ffff8880370d8558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff8880370d8558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7833
#2: ffff888036276950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.9.3067/14869: 3, on CPU#0:
#0: ffff88805b5c1088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:309
#1: ffff8880370d8558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff8880370d8558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7833
#2: ffff888036276950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.5.3089/14909: 3, on CPU#0:
#0: ffff88804fe46540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:548 [inline]
#0: ffff88804fe46540 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1dd/0x4e0 mm/util.c:579
#1: ffff8880370d8460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2281 [inline]
#1: ffff8880370d8460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff888036276950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.1.3079/14910: 3, on CPU#0:
#0: ffff88804fe45900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:548 [inline]
#0: ffff88804fe45900 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1dd/0x4e0 mm/util.c:579
#1: ffff8880370d8460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2281 [inline]
#1: ffff8880370d8460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff888036276950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:377 [inline]
watchdog+0x1073/0x10f0 kernel/hung_task.c:598
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245